A Simplified Account of Polymorphic References

A proof of the soundness of Tofte's imperative type discipline with respect to a structured operational semantics is given. The presentation is based on a semantic formalism that combines the bene ts of the approaches considered by Wright and Felleisen, and by Tofte, leading to a particularly simple proof of soundness of Tofte's type discipline. This research was sponsored by the Defense Advanced Research Projects Agency, CSTO, under the title \The Fox Project: Advanced Development of Systems Software", ARPA Order No. 8313, issued by ESD/AVS under Contract No. F19628-91-C-0168. The views and conclusions contained in this document are those of the author and should not be interpreted as representing o cial policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the U.S. Government.